JLG X19J Operator Manual - Manual (Page 61)

5.2 HAND PUMP
The hand pump (2) is used to pressurise oil for emergency movements made necessary by
any breakdown of the main hydraulic system.
The hand pump has a manual switch (1) used to select whether to control the two right sta‑
bilisers (Position A) or to control the two left stabilisers and the aerial part of the structure
(Position B).
5.3 SOLENOID VALVES FOR EMERGENCY DESCENT
The cylinders of the first‑second arm, of the third arm and the jib
have a solenoid valve for emergency descent (1). Activating the
emergency descent button on the remote control energises these
solenoid valves, which allow the descent of the aerial part of the
structure due to gravity.
The use of this emergency device depends on the platform’s
electrical system being powered.
5.4 SAFETY DEVICE BYPASS KEY
The machine has a key device that acts on the electrical circuit, bypassing the platform safety
systems. The device is situated on the cover of the electrical components compartment.
The use of this selector switch is illustrated in the following paragraphs on how to use the
machine.
0
6
0
4 0
2
00
1
2
A
B
1
X19JR0620113
BOOM LIFT MODELS X19J
JLG
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